CORRELATION BETWEEN DIAPHRAGM EXCURSION WITH BOTH THE QUALITY OF LIFE AND EXERCISE CAPACITY FOR PATIENTS WITH CHRONIC OBSTRUCTIVE PULMONARY DISEASE STUDIED BY ULTRASOUND

Abstract

Objective: To study the correlation between diaphragm excursion and both the quality of life and exercise capacity in patients with chronic obstructive pulmonary disease (COPD) by ultrasound and to reveal the factors affecting diaphragm excursion. Methods: A total of 42 COPD patients who were treated in our hospital from October 2015 to March 2020 and 42 healthy volunteers (control group) were included in the present study. The participants’ height, weight, and diaphragm excursion (the amplitude of diaphragm movement during deep breathing measured by M-mode ultrasound ([Formula: see text])), diaphragm movement time, degree of airflow obstruction (the forced expiratory volume in one second (FEV1) as a percentage of its predicted level, FEV1%pred), and exercise capacity (six-minute walk distance, 6MWD) were measured. The St. George’s Respiratory Questionnaire (SGRQ) was used to evaluate the patients’ quality of life. The correlation between the amplitude of diaphragm movement and lung function was analyzed. The receiver operating characteristics (ROC) curve was used to determine the COPD diagnosis efficacy of M-mode ultrasound, and its influencing factors were further analyzed. Results: During tidal breathing, the movement amplitudes of both hemidiaphragms in the COPD group were greater than those in the control group. During deep breathing, the movement amplitudes of both hemidiaphragms in the control group were greater than those in the COPD group. Moreover, during both tidal and deep breathing, the movement time of the right hemidiaphragm in the control group was longer than that in the COPD group (all P < 0.001). During deep breathing, the amplitude of diaphragm movement was positively correlated with FEV1 and FEV1%pred (both P < 0.001). During both tidal and deep breathing, the area under the ROC curve (AUC) for the diagnosis of COPD according to the diaphragm movement amplitude was 0.833 and 0.887, respectively, and the AUC for the diagnosis of COPD according to the diaphragm movement time was 0.625 and 0.732, respectively. The [Formula: see text] was correlated with the SGRQ score, symptom score, impact score, activity score, and 6MWD, with correlation coefficients of −0.474, −0.416, −0.432, −0.502, and 0.536, respectively. The factors affecting the [Formula: see text] were height ([Formula: see text], P < 0.001) and FEV1%pred ([Formula: see text], P < 0.001). Conclusion: The diaphragm excursion in COPD was closely related to patients’ quality of life. Height and FEV1%pred had the greatest impact on diaphragm excursion. The lower the diaphragm excursion of the patient, the worse their quality of life and the lower their exercise capacity.